Electric and Hybrid Electric Vehicles

Overview

With the growing demand from the world community to reduce the emission of carbon dioxide, and after more than a decade of intense research, electric vehicles (EVs) and hybrid electric vehicles (HEVs) suddenly appear more viable and necessary than ever before. These vehicles reduce, or eliminate, our reliance on fossil fuels. In EV's the propulsion system consists of an electric machine, power electronic circuitry, and a form of energy storage such as a battery or fuel cell. HEVs possess an internal combustion engine in addition to this electrical propulsion system. Regenerative braking and a downsizing of the internal combustion engine as compared to that of a conventional vehicle offer unprecedented possibilities to pursue higher fuel economy.

Fully realizing fuel economy benefits requires the design of electric machines and power electronic circuits with high performance and low cost. The energy management function of these advanced vehicles must also be carefully designed. Here energy management refers to the higher-level control algorithm that determines the flow of energy between the various components of the propulsion system.